1. Field of the Invention
This invention relates generally to problems with anchor bolts, and more particularly to reworking an improperly installed foundation bolt such that it extends a sufficient distance above attaching wood frame structure to meet local building codes.
2. Description of the Related Art
In home construction in California and other earthquake-prone areas, most local building codes require a large number of foundation bolts to tie the wood frame structure to the foundation. Since earthquakes introduce side loads into wood frame structures, the foundation bolts are needed to help prevent the house from moving off the foundation. Hurricanes pose similar threats and dictate the use of foundation bolts in the southeastern United States.
The foundation bolts are set every few feet into the concrete foundation before it hardens, and the wood frame structure is added. For a ⅝ inch diameter foundation bolt, the threaded end must extend at least ⅝ inch above the wood frame. If the foundation bolt fails to extend a sufficient distance, conventional practice is to drill into the concrete and properly install another foundation bolt, a labor-intensive task. Accordingly, a better way of dealing with an improperly installed foundation bolt is needed.
Others in the prior art have made certain related efforts to repair damaged anchor bolts or to utilize anchor bolts in new ways including in building construction, and the development of specialty hardware associated therewith, but those solutions have been less than satisfactory and appear generally inapplicable to the problem at hand. For example, Rowan Jr. U.S. Pat. No. 5,393,165 disclosed a bulky anchor bolt repair coupling held on by set screws or other engaging means. Klemic Jr. U.S. Pat. No. 4,872,298 disclosed various devices extending from an anchor bolt set in concrete. Weaver, U.S. Pat. No. 3,305,987 disclosed a nut device threaded onto a projecting bolt, and having a load bearing portion that fits into grooves in a ledger beam. Becker, U.S. Pat. No. 2,632,355 disclosed flanged nut hardware to engage a bolt disposed in a hole in a panel. Finally, Skidmore et, al. U.S. Pat. No. 5,890,332 disclosed a simple threaded sleeve for use with an anchor bolt to a steel rod.
The present invention addresses the problem at hand in a way not found or suggested in the prior art. Recall that an improperly installed foundation bolt is one having external threads protruding an insufficient distance above surrounding wood frame material for proper engagement of a conventional nut. A kit for reworking such foundation bolts includes a combination nut-sleeve having a continuous internal thread sized to engage the external thread of the foundation bolt. Further included is an elongate cap sized to cover the protruding external thread of the foundation bolt. The improper installation is reworked by covering the protruding foundation bolt with the cap, removing the material surrounding the foundation bolt with a conventional hole saw, and installing the threaded nut-sleeve combination onto the foundation bolt.
Preferably the length of the cap is slightly less than the internal length of the conventional hole saw, so as to maximize protection of the foundation bolt external threads as the surrounding material is removed at greater depths. The upper end of the cap preferably includes a transverse hole for facilitating removal of the cap from the foundation. A conventional hole saw sized to remove wood frame material from around the foundation bolt, and a conventional plate washer having a hole sized to accept the outside diameter of the elongate sleeve may also be included in the rework kit, although such materials would usually be available at most construction sites.
The method for reworking an improperly installed foundation bolt involves the placing a cap over the foundation bolt to protect the screw thread from damage, using a conventional hole saw to remove material surrounding the screw thread, removing the cap, and installing a combination threaded sleeve-nut onto the foundation bolt. The result is the length of possible engagement of the foundation bolt has been effectively extended, and the installation of the nut satisfactorily completed. The method also preferably includes installing a conventional plate washer onto the foundation bolt, prior to installing the combination threaded sleeve-nut.
It is an object of the present invention to provide a kit for reworking improperly installed foundation bolts, rather than having to install replacements.
It is a further object of the present invention to provide a method for reworking improperly installed foundation bolts, saving time and money over conventional methods.